Refactor input key reading

[tompng]

Simplify input key reading

Depends on #709
Second step of #708

We don't need complex read_2nd_character_of_key_sequence and read_escaped_key.

This source code commend is partially right (only for ESC keys), but not correct.

# GNU Readline waits for "keyseq-timeout" milliseconds to see if the ESC
# is followed by a character, and times out and treats it as a standalone
# ESC if the second character does not arrive. If the second character
# comes before timed out, it is treated as a modifier key with the
# meta-property of meta-key, so that it can be distinguished from
# multibyte characters with the 8th bit turned on.

Background

With this inputrc file

# .inputrc
"abcd": "[ABCD]"
"ab": "[AB]"

Input ab is :matched and also :matching (part of abcd). In this case, Readline waits for keyseq-timeout milliseconds.
Input abc is :matching (part of abcd). In this case, Readline waits forever.
It's not ESC specific nor 2nd-char specific.

Changes

1. Introduce another state :matching_matched for KeyStroke#match_status.
2. Refactor key reading. timeout will be matching_matched ? keyseq_timeout : Infinity.

[st0012]

This is a great simplification!

[st0012]

nit: can we please expand this, my brain isn't good enough to process nested ternary operators 😅

[tompng]

One test is failing (fails building native extension while installing io/console). I think it is not related to this change.

Passed job
https://github.com/tompng/reline/actions/runs/9377629652/job/25819506712

Set up job
  Runner Image
    Image: windows-2022
    Version: 20240514.3.0
Set up Ruby
  Print Ruby version
    ruby 3.4.0dev (2024-06-05T00:45:53Z master 63e9eaa5be) [x64-mswin64_140]

Failed job
https://github.com/ruby/reline/actions/runs/9377629917/job/25819752045

Set up job
  Runner Image
    Image: windows-2022
    Version: 20240603.1.0
Set up Ruby
  Print Ruby version
    ruby 3.4.0dev (2024-06-05T00:45:53Z master 63e9eaa5be) [x64-mswin64_140]

Same commit, same ruby version, different runner image verision.
I think ci on master branch will start failing soon. I ran ci in master https://github.com/ruby/reline/actions/runs/9377894574/job/25820174240 it passed maybe because it still uses windows-2022 ver: 20240514.3.0